Inhibitory effect of (-)-epigallocatechin gallate on titanium particle-induced TNF-alpha release and in vivo osteolysis.
	    		
		   		
		   			
		   		
	    	
    	 
    	10.3858/emm.2011.43.7.045
   		
        
        	
        	
        	
        		- Author:
	        		
		        		
		        		
			        		Shan JIN
			        		
			        		
			        		
			        			1
			        			
			        		
			        		
			        		
			        		
			        		;
		        		
		        		
		        		
			        		Ju Young PARK
			        		
			        		;
		        		
		        		
		        		
			        		Jung Min HONG
			        		
			        		;
		        		
		        		
		        		
			        		Tae Ho KIM
			        		
			        		;
		        		
		        		
		        		
			        		Hong In SHIN
			        		
			        		;
		        		
		        		
		        		
			        		Eui Kyun PARK
			        		
			        		;
		        		
		        		
		        		
			        		Shin Yoon KIM
			        		
			        		
		        		
		        		
		        		
		        		
		        			
			        		
			        		Author Information
			        		
		        		
		        		
			        		
			        		
			        			1. Skeletal Diseases Genome Research Center, Kyungpook National University Hospital, Kyungpook National University, Daegu 700-412, Korea. epark@knu.ac.kr, syukim@knu.ac.kr
			        		
		        		
	        		
        		 
        	
        	
        	
        		- Publication Type:Original Article ; Research Support, Non-U.S. Gov't
 
        	
        	
        		- Keywords:
        			
	        			
	        				
	        				
			        		
				        		epigallocatechin gallate;
			        		
			        		
			        		
				        		mitogen-activated protein kinases;
			        		
			        		
			        		
				        		transcription factor AP-1;
			        		
			        		
			        		
				        		NF-kappaB, titanium;
			        		
			        		
			        		
				        		tumor necrosis factor-alpha
			        		
			        		
	        			
        			
        		
 
        	
            
            	- MeSH:
            	
	        			
	        				
	        				
				        		
					        		Animals;
				        		
			        		
				        		
					        		Catechin/*analogs & derivatives/pharmacology;
				        		
			        		
				        		
					        		Cell Line;
				        		
			        		
				        		
					        		Implants, Experimental;
				        		
			        		
				        		
					        		Macrophages/drug effects/metabolism;
				        		
			        		
				        		
					        		Male;
				        		
			        		
				        		
					        		Mice;
				        		
			        		
				        		
					        		Mice, Inbred C57BL;
				        		
			        		
				        		
					        		Mitogen-Activated Protein Kinase 8/metabolism;
				        		
			        		
				        		
					        		NF-kappa B/metabolism;
				        		
			        		
				        		
					        		Osteolysis/chemically induced/*metabolism/prevention & control;
				        		
			        		
				        		
					        		Particulate Matter/*adverse effects;
				        		
			        		
				        		
					        		Prosthesis Failure;
				        		
			        		
				        		
					        		Signal Transduction/drug effects;
				        		
			        		
				        		
					        		Skull/*drug effects/pathology;
				        		
			        		
				        		
					        		Titanium/*adverse effects;
				        		
			        		
				        		
					        		Transcription Factor AP-1/metabolism;
				        		
			        		
				        		
					        		Tumor Necrosis Factor-alpha/*metabolism
				        		
			        		
	        			
	        			
            	
            	
 
            
            
            	- From:Experimental & Molecular Medicine
	            		
	            		 2011;43(7):411-418
	            	
            	
 
            
            
            	- CountryRepublic of Korea
 
            
            
            	- Language:English
 
            
            
            	- 
		        	Abstract:
			       	
			       		
				        
				        	Tumor necrosis factor-alpha (TNF-alpha) and inflammatory cytokines released from activated macrophages in response to particulate debris greatly impact periprosthetic bone loss and consequent implant failure. In the present study, we found that a major polyphenolic component of green tea, (-)-epigallocatechin gallate (EGCG), inhibited Ti particle-induced TNF-alpha release in macrophages in vitro and calvarial osteolysis in vivo. The Ti stimulation of macrophages released TNF-alpha in a dose- and time-dependent manner, and EGCG substantially suppressed Ti particle-induced TNF-alpha release. Analysis of signaling pathway showed that EGCG inhibited the Ti-induced c-Jun N-terminus kinase (JNK) activation and inhibitory kappaB (IkappaB) degradation, and consequently the Ti-induced transcriptional activation of AP-1 and NF-kappaB. In a mouse calvarial osteolysis model, EGCG inhibited Ti particle-induced osteolysis in vivo by suppressing TNF-alpha expression and osteoclast formation. Therefore, EGCG may be a potential candidate compound for osteolysis prevention and treatment as well as aseptic loosening after total replacement arthroplasty.